The SNP rs13720 (odds ratio [OR] = 2.15, 95% confidence interval [CI] = 1.58–2.94, P = 7.62 × 10−7), which is located in the 3′UTR of cathepsin Z (CTSZ), showed the strongest association with progression to jaundice stage in PBC. The gene discussed is CTSZ; the disease is primary biliary cholangitis.